Apparatus for forming a slide fastener



July 6, 1965 E. RYSER 3,192,566

APPARATUS FOR FORMING A SLIDE FASTENER Original Filed Jan. 23, 1961 5 Sheets-Sheet 1 Flg. 2 x 4 III 2 July 6, 1965 E. RYSER 3,192,566

APPARATUS FOR FORMING A SLIDE FASTENER Original Filed Jan. 23, 1961 3 Sheets-Sheet 2 Fig. 3

July 6, 1965 Original Filed Jan. 23, 1961 E. RYSER APPARATUS FOR FORMING A SLIDE FASTENER 3 Sheets-Sheet 5 United States Patent 3 192 566 APPARATUS son rain idle A sum; rAsrnNna Ernst Ryser, Mendrisio, Tessin, Switzerland, assignor of one-half to Bertrand Voumard, La Chaux-de-Fonds,

The present invention relates to apparatus for the manufacture of covered slide fasteners. The application is a divisional application of my application Ser. No. 84,008 filed Jan. 23, 1961, now US. Pat. 3,146,506 granted September 1, 1964.

In heretofore known covered slide fasteners having the fastener members formed directly on the longitudinal rim of the stringers by die-casting, the head of the fastener members, when viewed in the longitudinal direction of the fastener, is provided on one side with a wedge-shaped projection and on the other side with a corresponding recess. The stringer extends from the fastener member laterally of the head thereof. For the transverse locking of such fasteners, i.e. in order to prevent disengagement of the fastener members in a direction perpendicular to the plane of the fastener, projections are provided on the heads of the fastener members in the known fasteners in the form of abutment surfaces extending parallel to the stringer. This impairs to a certain extent the flexibility of the fastener in the transverse direction and requires the use of heads of substantial width.

To prevent the drawback of the known fasteners, the slide fastener according to the invention is provided at the side of each member head at which the stringer leaves the latter, with a first abutment surface, facing the fastener plane and inclined at an acute angle with respect to the longitudinal middle plane of the fastener and a second abutment surface opposite to the fastener plane and inclined with respect to the longitudinal middle plane at a complementary angle to the first-mentioned angle, the planes of these abutment surfaces intersecting each other at least approximatively in the longitudinal middle plane of the fastener.

For manufacturing such a slide fastener the stringers are laid in spaced relationship and in a manner known per se into recesses of one half of a two-part mould so as to be flush with the separating surface of the mould, whereafter the halves of the mould are superposed and the fastener members are cast from a casting gate arranged between the stringers onto the rims of the stringers facing each other. According to the invention, subsequent to the casting the mould half containing the head of the member is lifted from the other mould half together with the casting and the stringers whereafter the stringers are pushed away from the first-mentioned mould half up to the outlet at the fastener members and thereby the narrowed hollow space of the mould at the separating surface of the mould is opened for the complete length of the member, whereafter the casting is ejected from the first-mentioned mould half.

An object of the invention is to provide apparatus for carrying out the above described method, said apparatus comprising a two-part mould one half thereof having the hollow spaces for the head and for the larger'part of the base of the members of both rows of members, whereby a portion of the separating surface of the mould half comprising the hollow spaces for the member heads is formed at least approximatively by the front surface of other mould parts movably arranged at the body of the mould half said movable'mould parts narrowing from the side of the hollow space of the member head the hollow space of the mould at the separating surface thereof and forming a limiting surface of the hollow space for the member head extending in an acute angle to the plane of the mould separating surfaces extending between the mould spaces for the two rows of members, these mould parts, when the mould halves are separated, being movable out of their operating position to remove the mentioned narrowing in the mould space.

Other features and advantages of the invention will become apparent of the following description of an embodiment of a slide fastener and of apparatus for manufacturing same, given by Way of example only, reference being made to the accompanying drawings in which: r

FIG. 1 is a plan view showing a part of a slide fastener according to the invention; and

FIG. 2 is a cross-section through one half of the slide fastener shown in FIG. 1. a

FIG. 3 illustrates in a vertical cross-section an embodiment of a die-cast mould for manufacturing the slide fastener of FIGURES 1 and 2 and FIG. 4 illustrates a detail showing a modification 0 FIG. 3.

The covered slide fastener shown in FIGURES 1 and 2 comprises fastener members 2, made of metal or of any appropriate synthetic material die-cast directly on the single, bead-shaped longitudinal rim of the stringers 1. Each fastener member 2 has a base 2a enclosing the bead of the stringer and a head 2b arranged. laterally of the outlet in the base for the stringer. The head 21) has a leading edge projection 3 of triangular outline and a corresponding trailing edge recess 4. Furthermore, the head 21: is limited at its portion opposite the base 2a thereof with respect to the side of the stringerby an abutment surface 5 facing away from the base 2a and inclined at an angle a with respect to the longitudinal middle plane a of the fastener. A shelf 8 extends laterally from the base and partially extends within the trailing edge recess 4. The shelf includes an upper surface 6 which is inclined wth respect to the longitudinal middle plane a at an angle equal and opposite the surface 5 whereby planes containing said surfaces form a V-shape. The planes containing both mentioned surfaces intersect each other in a plane parallel to the longitudinal middle plane a of the fastener. However the line of intersection could also be included in the longitudinal middle plane a itself. The acute angle or preferably is between 20 and 40. 7

When the fastener is closed the surface 5 of all members 2 of one row of fastener members bears against the surface 6 of the shelf 8 of the corresponding members of the other row.

As is clearly visible from FIGURE 2 the guiding surface 7 which is closer to the head and serves to guide the stringer leaving the member base extends parallel to the abutment surface 6.

The two-part die-cast mould illustrated in FIGURE 4 and adapted to produce the slide fastener shown in FIG- URES l and 2 comprises an upper mould half 8 and a lower mould half 9. The separating surface between the two mould halves is planar. In the upper half 8 of the mould adapted for the simultaneous die-casting of both rows of fastener members of the fastener, there are provided spaces Ill for the formation of the member head 2b and of the larger portion of the member base 2a, while spaces 11 serve to mouldthe remainder portion of the member base. The recesses 12 permit insertion of the stringers in the lower mould half 9 in such manner that they are flush with the separating surface. The spaces 10 in the upper mould half 8 are narrowed at the separating surface of the mould half. This narrowing is obtained by a wedge-shaped mould plate 13 the front surface of which forms a portion of the separating surface of this mould half 8 and projects from the member head side into the space 16. Thereby this mould plate 13 forms an inner limiting surface 14 of the space extending at an acute angle to the separating surface of the mould. In the longitudinal middle of the upper mould half 8 there is secured in the latter and between the two rows of spaces 10 a lifting bolt 15 the end of which facing the separating surface of the mould is formed by a tap 17 of approximately pear shape and opening into a central mould space 16. One of the spaces 16 extending in the form of a channel over the length of all mould spaces 10 is connected through traverse channels 18 with said spaces 18 and is connected, when the mould is closed, with a casting space 19 in the lower mould half 9. The casting gate space 19 in turn is connected with the mouth of a die-cast nozzle 29 inserted into the latter mould half from the side opposite the separating surface.

The mould plates 13 of the upper mould half 8 are pivotally connected in a manner not shown with the main body of said mould half 8. The plane of pivoting of these mould plates 13 extends perpendicularly to the mould separating surface. Tensioning springs (not shown) normally hold the mould plate 13 in the represented working position. In the main body of the upper mould half 8 operating bolts 21 are arranged with their axes extending perpendicularly to the separating surface and bearing with their free, conical ends against the adjacent inner surface of the associated mould plate 13. An operating mechanism (not represented) is adapted to press the bolts 21 downwardly in their boring so that they come into the position shown in dot-and-dash lines in FIGURE 3 in which they have pivoted the mould plates 13 out of the working position thereof into the open position indicated in FIGURE 3 also by dot-anddash lines.

For producing the slide fastener shown in FIGURES 1 and 2 by means of the die-cast mould just described the operation is as follows. With the mould in open position the stringers 1 are laid into the recesses 12 of the lower mould half 9 such that the beads of the stringers 1 traverse the associated mould spaces 11 of the corresponding row. Thereby the upper side of the stringers when laid in the recesses 12 is flush with the separating surface between the mould halves. In the next following step the upper mould half 8 is placed on the lower mould half and the thus closed mould is locked.

The liquefied die-cast material (metal or synthetic material) is then introduced through the inlet nozzles 29 into the central channel 16 and from there the liquified material arrives through the traverse channels 18 into the mould spaces 10, 11. After the casting operation, the cast-in material completely fills the spaces 1%, 11, 18, 16 and 19 so as to form a single casting; After the hardening of the liquified material the mould is unlocked and the upper mould half 8 is removed from the lower mould half 9 by actuation of the lifting bolt 15. The casting which holds the stringers 1 remains in the upper mould half since the spaces 16 are narrow towards the separating surface by the mould plates 13 which prevent the casting from following from these spaces. Thereafter the bolts 21 are pressed downwardly in their borings resulting in a pivoting movement of the mould plates 13 to their inoperative position in which the narrowing of the mould space at the separating surface between the mould halves is eliminated.

Thereby it is possible to eject the casting from the upper mould half 8 by means of ejecting bolts (not represented) slidably arranged in borings of the upper mould half. Subsequently and in a conventional manner both rows of fasteners are separated by separating the members 4 from the webs of the casting formed in the transverse channels 18.

In the modification shown in FIGURE 4 the separating surface extends outside of the mould spaces It 11 and in an acute angle with respect to the plane including the separating surface between the two rows of spaces for the fastener members and projects into the lower mould half. The mould plates 13a are shaped correspondingly while the remainder of the mould is of the same construction as that shown in FIGURE 3.

The assembling and the separating of the mould and the removal of the casting for the modification in FIG. 4 is effected as described for the embodiment of FIGURE 3. However an advantage of this modification over the mould of FIGURE 3 resides in the fact that the stringers are already slightly deflected downwardly at the outlet of the member so that the folding of the stringers (indicated in dot-and-dash lines in FIGURE 2) required for the finishing of the slide fastener is somewhat facilitated.

As is visible, the inclined surface 14 of the mould plates (which of course project into the mould space It) only to the desired width) forms at the member head a correspondingly inclined abutting surface designated by 5 in FIGURES l and 2 and the mould surface for shaping the complementarily inclined abutment surface 6 at the main body is formed at the upper mould half 8.

Instead of being provided in the lower mould half the recesses adapted to receive the stringers 1 so that the latter lie'flush with the separating surface of the mould half could also be provided in the upper mould half 8. Consequently in this case the front surface of the mould plates 13 and 13a respectively would not be arranged to extend accurately in the separating surface of the mould but would rather be stepped back with respect to this separating surface by the thickness of the stringer.

I claim:

1. Apparatus for die-casting a covered slide fastener comprising a mold including first and second halves joined along a planar separating surface, each half having a recess cooperatively defining with the recess of the other half a cavity corresponding to the shape of the fastener members of the slide fastener, a mold plate movably supported in one of said halves and extending into the recess therein to bound and limit the same, said mold plate having a surface which extends in the plane of the separating surface, said mold plate having a further surface bounding and limiting the recess, the latter said surface being inclined with respect to said separating surface for forming said slide fastener with fastener members having an inclined surface which narrows towards the separating surface, and along which surface the fastener members rest on the mold plate, said mold plate being effective by virtue of the inclined surface thereof to sup port the thus cast fastener in said one half of the mold after the other half of the mold has been removed, and means for moving the mold plate away from the said one mold half to enable removal of the cast fastener.

2. Apparatus as claimed in claim 1 wherein said surface of the mold plate which bounds the recess is inclined acutely with respectto said separating surface.

3. Apparatus as claimed in claim 1 wherein said separating surface has an inclined portion at the location where the surface of the mold plate extends therealong.

4. Apparatus as claimed in claim 1 wherein said covered slide fastener comprises a fastener member and a stringer extending from the fastener member, one of said mold halves having a recess in which is accommodated the stringer such that the latter has a face extending along the separating surface.

5. Apparatus as claimed in claim 1 wherein the mold defines a pair of cavities one for each row of fastener members of the slide fastener and comprising a pair of of mold plates including the first said mold plate each associated with one of the cavities.

6. Apparatus for die-casting a covered fastener having a stringer and a fastener member attached to the stringer, said apparatus comprising a mold including first and second halves joined along a planar separating surface, each half having a recess co-operatively defining with the recess of the other half a cavity corresponding to the shape of the fastener member, one of the recesses corresponding to a major portion of the fastener member while the other of the recesses corresponds to a minor portion of the fastener member, a mold plate movably supported in said mold half which is provided the recess corresponding to the major portion of the fastener member, said mold plate having a surface extending in the plane of the separating surface, said mold piate further having an inclined surface bounding and limiting the recess in the associated mold half to define a cavity which narrows towards the separating surface whereby there will be formed a fastener member having an inclined surface narrowing towards the separating surface, the thus formed fastener members thereby resting on the inclined surface of the mold plate, said mold plate being effective by virtue of the inclined surface thereof to support the thus formed fastener member in the mold half associated with the mold plate after the other of the mold halves has been removed, and means for moving the mold plate relative to the associated mold half to enable removal of the cast fastener.

7. Apparatus as claimed in claim 6 wherein the mold half associated with the mold plate is located above the other of the mold halves and the mold plate surface 6 which bounds said recess therein is inclined acutely with respect to said separating surface and causes narrowing of said recess in a downwardly direction.

8. Apparatus as claimed in claim 6 wherein the sur- 5 face of the mold plate which extends along the separating surface is constituted by an end surface of the mold plate.

9. Apparatus as claimed in claim 6 wherein said mold plate is pivota'ole in a plane perpendicular to the separating surface of the mold halves.

10. Apparatus as claimed in claim 6 wherein the separating surface extends acutely from the cavity defined by said recesses.

11. Apparatus as claimed in claim 6 wherein the means for moving the mold plate comprises a movable bolt contacting the mold plate for moving the same therewith, the bolt being movably supported within an opening provided in the mold half associated with the mold plate.

References Qited by the Examiner UNITED STATES PATENTS 2,426,408 8/47 Morin 18--30 05 2,502,860 4/50 Leithiser 1859 2,543,111 2/51 Kuzmick 1830 2,742,670 4/56 Morin 18-30 2,759,223 8/56 Del Camp 13-59 V/ILLIAM J. S'lEPI-IENSON Primary Examiner.

ROBERT F. WHIT E, MICHAEL V. BRINDISI,

Examiners. 

1. APPARATUS FOR DIE-CASTING A COVERED SLIDE FASTENER COMPRRISING A MOLD INCLUDING FIRST AND SECOND HALVES JOINED ALONG A PLANAR SEPARATING SURFACE, EACH HALF HAVING A RECESS COOPERATIVELY DEFINING WITH THE RECESS OF THE OTHER HALF A CAVITY CORRESPONDING TO THE SHAPE OF THE FASTENER MEMBERS OF THE SLIDE FASTENER, A MOLD PLATE MOVABLY SUPPORTED IN ONE OF SAID HALVES AND EXTENDING INTO THE RECESS THEREIN TO BOUND AND LIMIT THE SAME, SAID MOLD PLATE HAVING A SURFACE WHICH EXTENDS IN THE PLANE OF THE SEPARATING SURFACE, SAID MOLD PLATE HAVING A FURTHER SURFACE BOUNDING AND LIMITING THE RECESS, THE LATTER SAID SURFACE BEING INCLINED WITH RESPECT TO SAID SEPARATING SURFACE FOR FORMING SAID SLIDE FASTENER WITH FASTENER MEMBERS HAVING AN INCLINED SURFACE WHICH NARROWS TOWARDS THE SEPARATING SURFACE, AND ALONG WHICH SURFACE THE FASTENER MEMBERS REST ON THE MOLD PLATE, SAID MOLD PLATE BEING EFFECTIVE BY VIRTUE OF THE INCLINED SURFACE THEREOF TO SUPPORT THE THUS CAST FASTENER IN SAID ONE HALF OF THE MOLD AFTER THE OTHER HALF OF THE MOLD HAS BEEN REMOVED, AND MEANS FOR MOVING THE MOLD PLATE AWAY FROM THE SAID ONE MOLD HALF TO ENABLE REMOVAL OF THE CAST FASTENER. 